diff options
Diffstat (limited to 'Documentation/sound/alsa-configuration.rst')
| -rw-r--r-- | Documentation/sound/alsa-configuration.rst | 147 |
1 files changed, 114 insertions, 33 deletions
diff --git a/Documentation/sound/alsa-configuration.rst b/Documentation/sound/alsa-configuration.rst index 21ab5e6f7062..0a4eaa7d66dd 100644 --- a/Documentation/sound/alsa-configuration.rst +++ b/Documentation/sound/alsa-configuration.rst @@ -58,7 +58,7 @@ debug 2 = verbose debug messages); This option appears only when ``CONFIG_SND_DEBUG=y``. This option can be dynamically changed via sysfs - /sys/modules/snd/parameters/debug file. + /sys/module/snd/parameters/debug file. Module snd-pcm-oss ------------------ @@ -70,7 +70,7 @@ dsp_map PCM device number maps assigned to the 1st OSS device; Default: 0 adsp_map - PCM device number maps assigned to the 2st OSS device; + PCM device number maps assigned to the 2nd OSS device; Default: 1 nonblock_open Don't block opening busy PCM devices; @@ -97,7 +97,7 @@ midi_map MIDI device number maps assigned to the 1st OSS device; Default: 0 amidi_map - MIDI device number maps assigned to the 2st OSS device; + MIDI device number maps assigned to the 2nd OSS device; Default: 1 Module snd-soc-core @@ -133,6 +133,19 @@ enable enable card; Default: enabled, for PCI and ISA PnP cards +These options are used for either specifying the order of instances or +controlling enabling and disabling of each one of the devices if there +are multiple devices bound with the same driver. For example, there are +many machines which have two HD-audio controllers (one for HDMI/DP +audio and another for onboard analog). In most cases, the second one is +in primary usage, and people would like to assign it as the first +appearing card. They can do it by specifying "index=1,0" module +parameter, which will swap the assignment slots. + +Today, with the sound backend like PulseAudio and PipeWire which +supports dynamic configuration, it's of little use, but that was a +help for static configuration in the past. + Module snd-adlib ---------------- @@ -723,13 +736,14 @@ Module for EMU10K1/EMU10k2 based PCI sound cards. * Sound Blaster Live! * Sound Blaster PCI 512 -* Emu APS (partially supported) * Sound Blaster Audigy - +* E-MU APS (partially supported) +* E-MU DAS + extin - bitmap of available external inputs for FX8010 (see bellow) + bitmap of available external inputs for FX8010 (see below) extout - bitmap of available external outputs for FX8010 (see bellow) + bitmap of available external outputs for FX8010 (see below) seq_ports allocated sequencer ports (4 by default) max_synth_voices @@ -1045,6 +1059,9 @@ power_save Automatic power-saving timeout (in second, 0 = disable) power_save_controller Reset HD-audio controller in power-saving mode (default = on) +pm_blacklist + Enable / disable power-management deny-list (default = look up PM + deny-list, 0 = skip PM deny-list, 1 = force to turn off runtime PM) align_buffer_size Force rounding of buffer/period sizes to multiples of 128 bytes. This is more efficient in terms of memory access but isn't @@ -2236,8 +2253,15 @@ device_setup Default: 0x0000 ignore_ctl_error Ignore any USB-controller regarding mixer interface (default: no) + ``ignore_ctl_error=1`` may help when you get an error at accessing + the mixer element such as URB error -22. This happens on some + buggy USB device or the controller. This workaround corresponds to + the ``quirk_flags`` bit 14, too. autoclock Enable auto-clock selection for UAC2 devices (default: yes) +lowlatency + Enable low latency playback mode (default: yes). + Could disable it to switch back to the old mode if face a regression. quirk_alias Quirk alias list, pass strings like ``0123abcd:5678beef``, which applies the existing quirk for the device 5678:beef to a new @@ -2267,29 +2291,87 @@ delayed_register The driver prints a message like "Found post-registration device assignment: 1234abcd:04" for such a device, so that user can notice the need. +skip_validation + Skip unit descriptor validation (default: no). + The option is used to ignore the validation errors with the hexdump + of the unit descriptor instead of a driver probe error, so that we + can check its details. quirk_flags - Contains the bit flags for various device specific workarounds. - Applied to the corresponding card index. - - * bit 0: Skip reading sample rate for devices - * bit 1: Create Media Controller API entries - * bit 2: Allow alignment on audio sub-slot at transfer - * bit 3: Add length specifier to transfers - * bit 4: Start playback stream at first in implement feedback mode - * bit 5: Skip clock selector setup - * bit 6: Ignore errors from clock source search - * bit 7: Indicates ITF-USB DSD based DACs - * bit 8: Add a delay of 20ms at each control message handling - * bit 9: Add a delay of 1-2ms at each control message handling - * bit 10: Add a delay of 5-6ms at each control message handling - * bit 11: Add a delay of 50ms at each interface setup - * bit 12: Perform sample rate validations at probe - * bit 13: Disable runtime PM autosuspend - * bit 14: Ignore errors for mixer access - * bit 15: Support generic DSD raw U32_BE format - * bit 16: Set up the interface at first like UAC1 - * bit 17: Apply the generic implicit feedback sync mode - * bit 18: Don't apply implicit feedback sync mode + The option provides a refined and flexible control for applying quirk + flags. It allows to specify the quirk flags for each device, and can + be modified dynamically via sysfs. + The old usage accepts an array of integers, each of which applies quirk + flags on the device in the order of probing. + E.g., ``quirk_flags=0x01,0x02`` applies get_sample_rate to the first + device, and share_media_device to the second device. + The new usage accepts a string in the format of + ``VID1:PID1:FLAGS1;VID2:PID2:FLAGS2;...``, where ``VIDx`` and ``PIDx`` + specify the device, and ``FLAGSx`` specify the flags to be applied. + ``VIDx`` and ``PIDx`` are 4-digit hexadecimal numbers, and can be + specified as ``*`` to match any value. ``FLAGSx`` can be a set of + flags given by name, separated by ``|``, or a hexadecimal number + representing the bit flags. The available flag names are listed below. + An exclamation mark can be prefixed to a flag name to negate the flag. + For example, ``1234:abcd:mixer_playback_min_mute|!ignore_ctl_error;*:*:0x01;`` + applies the ``mixer_playback_min_mute`` flag and clears the + ``ignore_ctl_error`` flag for the device 1234:abcd, and applies the + ``skip_sample_rate`` flag for all devices. + + * bit 0: ``get_sample_rate`` + Skip reading sample rate for devices + * bit 1: ``share_media_device`` + Create Media Controller API entries + * bit 2: ``align_transfer`` + Allow alignment on audio sub-slot at transfer + * bit 3: ``tx_length`` + Add length specifier to transfers + * bit 4: ``playback_first`` + Start playback stream at first in implement feedback mode + * bit 5: ``skip_clock_selector`` + Skip clock selector setup + * bit 6: ``ignore_clock_source`` + Ignore errors from clock source search + * bit 7: ``itf_usb_dsd_dac`` + Indicates ITF-USB DSD-based DACs + * bit 8: ``ctl_msg_delay`` + Add a delay of 20ms at each control message handling + * bit 9: ``ctl_msg_delay_1m`` + Add a delay of 1-2ms at each control message handling + * bit 10: ``ctl_msg_delay_5m`` + Add a delay of 5-6ms at each control message handling + * bit 11: ``iface_delay`` + Add a delay of 50ms at each interface setup + * bit 12: ``validate_rates`` + Perform sample rate validations at probe + * bit 13: ``disable_autosuspend`` + Disable runtime PM autosuspend + * bit 14: ``ignore_ctl_error`` + Ignore errors for mixer access + * bit 15: ``dsd_raw`` + Support generic DSD raw U32_BE format + * bit 16: ``set_iface_first`` + Set up the interface at first like UAC1 + * bit 17: ``generic_implicit_fb`` + Apply the generic implicit feedback sync mode + * bit 18: ``skip_implicit_fb`` + Don't apply implicit feedback sync mode + * bit 19: ``iface_skip_close`` + Don't close interface during setting sample rate + * bit 20: ``force_iface_reset`` + Force an interface reset whenever stopping & restarting a stream + * bit 21: ``fixed_rate`` + Do not set PCM rate (frequency) when only one rate is available + for the given endpoint + * bit 22: ``mic_res_16`` + Set the fixed resolution 16 for Mic Capture Volume + * bit 23: ``mic_res_384`` + Set the fixed resolution 384 for Mic Capture Volume + * bit 24: ``mixer_playback_min_mute`` + Set minimum volume control value as mute for devices where the + lowest playback value represents muted state instead of minimum + audible volume + * bit 25: ``mixer_capture_min_mute`` + Similar to bit 24 but for capture streams This module supports multiple devices, autoprobe and hotplugging. @@ -2297,10 +2379,9 @@ NB: ``nrpacks`` parameter can be modified dynamically via sysfs. Don't put the value over 20. Changing via sysfs has no sanity check. -NB: ``ignore_ctl_error=1`` may help when you get an error at accessing -the mixer element such as URB error -22. This happens on some -buggy USB device or the controller. This workaround corresponds to -the ``quirk_flags`` bit 14, too. +NB: ``ignore_ctl_error=1`` just provides a quick way to work around the +issues. If you have a buggy device that requires these quirks, please +report it to the upstream. NB: ``quirk_alias`` option is provided only for testing / development. If you want to have a proper support, contact to upstream for |